String-instrument tuning peg



Aug. 20, 1929.

Filed Aargh s1, '1927 Patented Aug. 20, 1929.

UNITED STATES JOHN F. NELSON, 0F FOREST PARK, ILLINOIS.

STRING-INSTRUMENT TUNING PEG.

Application tiled March 31, 1927.

This invention relates to means for adjustably tightening the strings of pianos, mandolins, harps and other stringed instruments.

The object of the invention is to provide a string retaining post or peg of such a construction and so mounted that when the peg is manually turned to a desired point for tensioning the particular string controlled by that peg, said peg will stay in the rotated position without returning or back-lashing, thereby insuring the maintenance of the special tension which the operator has put on the string or wire of the instrument to give it the desired tone.

The invention consists in a device capable of attaining the foregoing and other objects; which can be easily and cheaply made; which is very satisfactory in use and is not -readily liable to get out of order.

More particularly the invention consists in numerous features and details hereafter more fully set forth in the specification and claims.

Referring to the drawings, in which like numbers represent the same parts throughout the several views:

Figure l is a face view of a portion of the lsounding board mechanism of a musical instrument, showing the mounting of a plurality of wires whose tension and consequent tuning is controlled by devices of this 1nvention.

Figure 2 is a sectional, detail view on the irregular line 2-2 of Figure 1. v

Figure 3 is a perspective view of the d1sassembled parts of a tuning peg of this invention.

Figure 1 of the drawings shows a multiplicity of wires or strings 10 having fixed ends 12 non-adjustably secured to pins or posts 14 on one board or other part 16 of the musical instrument.

The opposite end of each wire 10 passes through a hole 18 in a tuning peg 2O of this invention rotatively mounted on another board 22 or other member of a musical instrument. Intermediate between the ends of these wires or strings 10, they pass over conventional pins 24 and 26 clearly shown in Figures 1 and 2. The wires 10 are at a suitable point conventionally engaged by the bridge 28.

The essential problem of this invention is to so construct each pin 20 that when the operator applies a wrench or other tuning tool, not shown, to the non-circular end 30 of a Serial No. 180,037.

given peg and rotates it within the conical recess 32 provided for it in the board or block 22 to thereby tension a particular wire 10 controlled by that peg, the peg will by frictional engagement with the wall of the conical recess 32 remain in adjustment without reversey or back-lash motion when the operator removes his wrench from the end 30 of said peg. This desired result is accomplished by locating the larger end 34 of the peg within a cylindrical recess 36 in the board or base 22, there being within said recess 36 a mechanism of special construction for forcing the conical pin 20 into engagement with the conical wall 32 in the board or base 22.

The forcing mechanism just referred to includes a longitudinally reciprocal pin 38 having a hemispherical, metallic head 40 rotatably engaging a hemispherical recess 42 in the base 34 of the peg 20, said pin 38 being constantly urged into engagement with said peg by coil spring 44 embracing the pin 38 and bearing at one end against the under side of the head 40, while the other end of said spring takes bearing at the bottom of an intei-nal recess 4G in a rotatable plug 48, screwthreaded into the recess 36, heretofore referred to.

The construction of the plug 48 is of considerable importance in that it has an enlarged head 50 of greater diameter than the recess 36 in the board 22, there being between the head 5() and the screw threads 52 a. square shoulder 54 bearing against the rear surface 56 of member 22, with the result that when an operator rotates plug 48, as for instance by placing a suitable instrument in the noncircular opening 58 in the end thereof and turns said plug tightly to the position shown, particularly in the upper portion of Fig. 2, the plug will be so tightly fastened in the board 22 that rotation of the peg 2O and consequent possible rotation of the spring 44 does not in any way disturb, viz rotate the plug 48.

For successful operation of the mechanism of this invention, it is highly desirable that at least the head 40 of the pin 38 be of metal so that there is insured an actual rotation of the peg 2O with reference to said head 40 and not the well known mere twisting of the parts; more or less internal twisting; which takes place where these parts are wood as has heretofore been the practice-for, when the parts are of wood, said internal twisting causes a reverse or back-lash motion under the tension of the twined wire l0 when the operator, after tightening the wire, removes his wrench or the like from non-circular portion of peg 20.

It is highly desirable, though not absolutely necessary, that the conical surface of peg 2() lbe given a thin film of a suitable paint having lubricating characteristics, as for inand having a string engaging portion adapted to extend from said stationary member, a hollow rotatable plug screw threaded into the larger end of the stationary member, a spring )in the hollow portion of the plug adjacent to stance a graphic paint before it is inserted in -the position shown in Figure 2, such paint having a lubricating effect upon the pin 2O without the numerous well known disadvantages which occur when oil is used, the chief of Which is the tendency of the peg to jump when the string being tuned is under tension.

This jumping action77 is caused by the tendency of the tuning peg to move in jerks an d by a series of minute steps, instead of smoothly and evenly, when the peg is rotated while carrying a string under tension and renders the accurate tuning of a string associated with a jumpy peg extremely dicult.

By the use of mechanism constructed in accordance with this invention and particularly when a lubricating paint is used between the plug '2O and the conical wall 32 of the board '20, instruments equipped with this iiivention can be tuned to desired tone without v the wires or strings so tuned slipping back v0l after the tuner removes his wrench from the non-.circular portions 2() of the tuning peg. It will be noted that the plug 48 is hollow the peg, a bearing member normally urged by the spring intoengagement with said end of the peg, whereby the peg is normally urged to seat within said perforation.

l. In a timing peg construction, the combination of a stationary member having a perforation formed therein, said perforation having a conical portion and a cylindrical portion, a rotatable peg having a conical portion seating in the conical portion of said perforation and having a string engaging portion extending from said stationary member, a hollow rotatable plug threaded into the cylindrical portion of the perforation I below the plug, a spring arranged in the hollow portion of the plug adjacent the rotatable peg, a metallic bearing member arranged between the spring and the conical portion of the peg, the spring being adapted to react be-` j tween said plug and said bearing member to and this fact permits adjustments of the peg l to be made by tapping the lower end of the member l0 by means of a punch inserted yllhis adjustment may through the plug 48. be necessary where the film of paint is unlevenly applied or where for any reason the peg has not seated properly, it ing understood that the peg may thus be properly' seated without removing the plug, spring and n member 4:0.

Having thus described my invention, whatA I claim asl new and desire to describe as Letters Patent is:

l. In a tuning peg construction, m combination, a stationary member having a conical perforation therein, a conical peg rotatable inv said perforation, a metal bearing member engaging the larger end of the conical peg and Y resilient means acting through the bearing member urging the peg into engagement with the conical walls of the stationary member.

2. In a tuning peg construction, in combination, a stationary member having a perforation therein, a peg rotatable in said perforation, said peg having a socket formed in one end, a metal bearing member engaging the,

socketof the peg and resilient means acting through the bearing member to urge the peg into engagement with the stationary member.

3. In a tuning peg construction, in combij nation, a stationary member having a conical Y perforation, a conical rotatable peg having a portion arrangeable within said perforation ranged in said perforation below said bearing member, and resilient means reacting between said plug and said bearing member whereby the latterl is urged into the socket.

6. In a timing peg construction, in combi'- nation, a stationary member having a conical perforation therein, said perforation having a conical portion, a conical peg rotatably mounted in said perforation, said peg hav? ing a string engaging portion at one end and a socket formed in the other end, a `metal bearing member engaging in said socket, a plug arranged in said perforation below said bearing member and resilient means react-ing between said plug and'said bearing member vwhereby the latter is urged into the socket,

said plug being provided with a non-circular aperture whereby it may be rotated, by means of a suitable instrument to secure itin place in the perforation.

7. In a tuning peg construction, in combi-Y nation, a stationary member having perfora- Y tion, said perforation having a conical portion, a conical peg rotatably mounted in said erforationsaid ev havin astrino en0fa0= 7 b CJ D 25 ing portion at one end and a socket formed at the other end, a metalbearing member engaging said socket, a plug arranged in said perforation below said bearing member, resilient means reacting between said plug and said bearing member whereby the latter is urged into the socket, and means for rotating the plug, the plug being provided with a square shoulder and screw threads whereby to secure it in the aperture and lock it against accidental rotation by engagement of said shoulder and stationary member at the lower end of said perforation.

8. In a tuning peg construction, in combination, a stationary member having a perforation, a peg adapted to seat in the perforation and having an end formed to provide a bearing surface within the perforation, a bearing member engaging said bearing surface and resilient means reacting between the stationary member and the bearing member whereby to normally urge the peg longitudinally to seated position in the perforation.

9. In a tuning peg construction, in combination, a stationary member having a perforation, a peg adapted to seat in the perforation and having an end formed to provide a bearing surface within the perforation, a

bearing member engaging said bearing surface, a plug arranged in Said perforation below said peg and resilient means reacting between said plug and the bearing member whereby to normally urge the peg to seated position in the perforation.

10. In a tuning peg construction, in combination, a stationary member having a perforation, a peg adapted to seat in the perforation and having an end formed to provide a bearing surface within the perforation, a bearing member engaging said bearing surface of the peg, a plug arranged in said perforation below said peg and resilient means reacting between said plug and the bearing member whereby to normally urge the peg to seated position in the perforation, said plug being suitably socketed to provide means whereby said plug may be engaged by an instrument for rotating the same.

In witness whereof, I have hereunto subscribed my name.

JoHN F. NE'LsoN. 

